Thursday, November 27, 2008

CNET Interviews N-trig

CNET does a story about an interview with Lenny Engelhardt, N-trig's VP of Business Development.

He said "Seven- to 17-inches is our sweet spot" since screens of smart phones and other small mobile devices are too small to make a good multitouch interface.

My opinion is a little different. First, Apple iPhone anyway has shown an excellent way of applying multitouch to small screen devices. Second, I think that N-trig's DuoSense is much more important feature than multi-touch. With DuoSense technology, a user can use pen and multi-touch simultaneously. Pen input is very important feature for Chinese users due to their complex character system (ideogram).

So, I slightly modified N-trig's opinion: 1) seven- to 17-inches is a sweet spot of multi-touch and 2) cell-phones and smart phones are a sweet spot for DuoSense.


Wednesday, November 26, 2008

DIY Capacitive Touch Sensing III, with Arduino

In Arduino forum, you can find discussions on making a capacitive touch sensor with Arduino platform. Arduino is an open source electronics prototyping platform for artists, designers, and many others.

Beside touch sensing, Arduino forum has discussions on many interesting hobby projects. The figure below is Pololu 3pi Line Maze Solving Robot.

Pololu 3pi Line Maze Solving Robot

Tuesday, November 25, 2008

DIY Multi-touch Gesture

Multitouch Applications from Falcon4ever on Vimeo. is a multi-touch and multi-gesture research blog by Laurence Muller. He developed a multi-touch system called tDesk. He also obtained MS degree for the multi-touch interface. His master thesis is well organized and covers various aspects of multi-touch systems, from system design to user study. For me, Chapter 3: Multi-touch detection and processing is quite useful to understand the internal data processing of multi-touch systems. If you are to make your own multi-touch gesture software, the thesis is worth while to study.

DIY Capacitive Touch Sensing II


Previously, I posted an article on DIY capacitive touch sensing. Today I found another interesting site - CapToolKit - helpful to make your own capacitive touch sensor. The site is maintained by Raphael Wimmer and contains everything - schematics, firmware, communication protocol, etc., to build capacitive touch sensing applications.

Monday, November 24, 2008

Microchip's new inductive touch-sensing technology

Microchip has a new line of touch sensing products called "inductive touch". Let me show their introduction rather than mine.

When a user presses the front panel, it deflects slightly. This deflection, on the order of microns, is inductively detected. The fundamental principle of operation is that the impedance of an inductor varies when a nearby magnetically permeable or electrically conductive material moves relative to the inductor.

Inductive Touch

As you shown from the above description and illustration, it's a kind of a pressure sensor while most capacitive touch sensors are categorized as contact sensors. It senses the change of distance between two parallel plates when a user presses down the sensor. In my opinion, the term touch now has three different meanings: contact, pressure, and proximity. There are many ways to construct a pressure sensor using various sensing techniques. The most popular but people are not aware is resistive touch screen. Capacitance sensing technique can also be used to pressure sensors (You can find an example in PPS web site).

Here, I have a question. The Microchip's document shows a comparison chart that compares inductive touch and capacitive touch. But I'd like to know differences between capacitive pressure sensing and inductive pressure sensing (inductive touch). There should be some differences, but I couldn't identify since I'm not so familiar with pressure sensing. Does anybody know an answer?

Comparison between inductive touch and capacitive touch

Sunday, November 16, 2008

Multi-touch resources

Multitouch SDKs, APIs, and Applications





The owner says:

This is the web-page of my recent multi-touch software project.

It was born from an entry to the well-known german "Jugend forscht" technical & scientific youth-contest. This work won the regional-contest of Unterfranken at March 9, 2007 and next level, the bavarian-contest in Munich at March 29. From May 17. to 20. it could be seen in Hamburg and won the second prize. At CeBIT 2008 the prototype of mehr:wert could be seen at Hall 9, Stand B40.




PQWindow Software Platform adds Multi-Touch foundations to various operating systems such as Windows, Mac OS, etc. The package also comes with valuable Mulit-Touch applications to show case innovative human computer interactions.



MultiMouse is a Windows multi-touch mouse driver developed using touchlib


image image


Articles helpful to develop multi-touch applications

The article describes how to enable multitouch gestures using IBM ThinkPad T30 equipped with a Synaptics TouchPad. The supporting multitouch gestures include 'three-finger swipe' and open- and close-pinch geestures.

Monday, November 10, 2008

MOMO: Haptic Navigation Aid

Momo gives directions to people by haptic feedback. The user holds the device and it tilts and vibrates to give right way to go.

momo: a haptic navigation device from kristin on Vimeo.

Link: MAKE

Wednesday, November 5, 2008

Do people really like multi touch?

image image
He noted Microsoft's touch interface as an important element in this strategy.
"This [touch] is becoming a big opportunity for everybody," Sinofsky said.
Sensor development was also emphasized during the keynote address. Microsoft is giving away sensor development kits at WinHEC while they last. Sinofsky noted that touch sensor hardware is currently being shipped.

Monday, November 3, 2008


Force, Pressure, and Touch -
Force pressure touch technology: FSR sensor, electronics, firmware and software
Design Service Low Cost Pressure Mapping
Related Posts with Thumbnails